Document Cloud Run Public Preview and combined SDK samples

docs/develop/dotnet/workers/serverless-workers/cloud-run.mdx

@@ -15,15 +15,13 @@ tags:
 import { ReleaseNoteHeader } from '@site/src/components';
 
 <ReleaseNoteHeader featureName="serverlessWorkersCloudRun">
-  Cloud Run support is in Pre-release, and its APIs may change in backwards-incompatible ways.
-  Create a [support ticket](/evaluate/cloud/support#support-ticket) or contact your account team for access, and
-  [sign up for updates](https://temporal.io/pages/serverless-workers-updates) to hear when Cloud Run reaches Public Preview.
+  Cloud Run support is in Public Preview. APIs and configuration may change before the stable release.
 </ReleaseNoteHeader>
 
 On a [GCP Cloud Run worker pool](https://cloud.google.com/run/docs/resource-model#worker-pools), you run a standard long-lived Temporal Worker.
 Register Workflows and Activities the same way you would with any other .NET Worker, and Temporal Cloud scales the pool up and down as work arrives and drains.
 
-A Cloud Run Worker needs no Cloud Run-specific package.
+A Cloud Run Worker needs no Cloud Run-specific runtime or handler.
 The one addition to a standard Worker is [Worker Versioning](/worker-versioning), which is required for Serverless Workers.
 
 For the end-to-end deployment guide covering the Worker Pool, IAM, and compute configuration, see [Deploy a Serverless Worker on GCP Cloud Run](/production-deployment/worker-deployments/serverless-workers/cloud-run).
@@ -135,7 +133,50 @@ public static string Process(IReadOnlyList<string> items)
 
 For how scale-in decisions are made, see [Serverless Workers on GCP Cloud Run](/serverless-workers/cloud-run#lifecycle).
 
-## Add observability {/* #add-observability */}
+## Configure OpenTelemetry {/* #opentelemetry */}
 
-A Cloud Run Worker emits the same traces and metrics as a Worker anywhere else.
-For how to configure metrics export and OpenTelemetry tracing interceptors, see [Observability - .NET SDK](/develop/dotnet/platform/observability) and the [SDK metrics reference](/references/sdk-metrics).
+Run an OpenTelemetry Collector as a sidecar in the Worker Pool. Call `ApplyGoogleCloudRunOpenTelemetryDefaults()`
+to configure tracing and Temporal Core metrics for OTLP export to the Collector at `localhost:4317`. Load the Client
+connection settings with `ClientEnvConfig.LoadClientConnectOptions()`, then configure both plugins before connecting:
+
+<!--SNIPSTART dotnet-cloud-run-->
+[src/Gcp/CloudRun/Program.cs](https://github.com/temporalio/samples-dotnet/blob/gcp-cloud-run/src/Gcp/CloudRun/Program.cs)
+```cs
+// The Cloud Run Id plugin sets the client identity to "{instanceId}@{revision}" from Cloud Run
+// metadata at connect time; every Worker created from the client inherits it.
+connectOptions.Plugins = new ITemporalClientPlugin[] { new CloudRunIdPlugin() };
+
+// ApplyGoogleCloudRunOpenTelemetryDefaults adds the tracing interceptor and a runtime exporting Core
+// metrics + traces over OTLP to the collector sidecar; the returned handle owns the tracer provider.
+// Both plugins configure the same connect options.
+using var telemetry = connectOptions.ApplyGoogleCloudRunOpenTelemetryDefaults();
+
+var client = await TemporalClient.ConnectAsync(connectOptions);
+```
+<!--SNIPEND-->
+
+After the Worker stops, call `telemetry.FlushAsync(TimeSpan.FromSeconds(2))` to flush traces within the Cloud Run
+termination window. For the Collector sidecar configuration and deployment steps, see the
+[.NET Cloud Run sample](https://github.com/temporalio/samples-dotnet/tree/gcp-cloud-run/src/Gcp/CloudRun).
+
+## Set a Worker identity {/* #worker-identity */}
+
+Use `CloudRunIdPlugin` to identify each Worker instance as `<instance-id>@<revision>`. The plugin reads Cloud Run environment variables and instance metadata when the Client connects, then Workers created from that Client inherit the identity.
+
+Register the plugin on the Client options before connecting:
+
+```csharp
+using Temporalio.Client;
+using Temporalio.Common.EnvConfig;
+using Temporalio.Extensions.Gcp.CloudRun.Id;
+
+// ...
+    var connectOptions = ClientEnvConfig.LoadClientConnectOptions();
+    connectOptions.Plugins = new ITemporalClientPlugin[] { new CloudRunIdPlugin() };
+    var client = await TemporalClient.ConnectAsync(connectOptions);
+    // ...
+```
+
+The [preceding example](#opentelemetry) registers `CloudRunIdPlugin` alongside the OpenTelemetry defaults.
+
+The plugin requires the Cloud Run metadata server, so it fails when the Worker runs outside Cloud Run. For a complete example, see the [.NET Cloud Run sample](https://github.com/temporalio/samples-dotnet/tree/gcp-cloud-run/src/Gcp/CloudRun).

docs/develop/dotnet/workers/serverless-workers/index.mdx

@@ -14,10 +14,7 @@ tags:
 import { ReleaseNoteHeader } from '@site/src/components';
 
 <ReleaseNoteHeader type="publicPreview">
-  AWS Lambda support is in Public Preview. GCP Cloud Run support is in Pre-release, and its APIs may change in
-  backwards-incompatible ways. To request Cloud Run access, create a [support ticket](/evaluate/cloud/support#support-ticket) or
-  contact your account team, and [sign up for updates](https://temporal.io/pages/serverless-workers-updates) to hear
-  when Cloud Run reaches Public Preview.
+  AWS Lambda and GCP Cloud Run support are in Public Preview.
 </ReleaseNoteHeader>
 
 Serverless Workers run on ephemeral, on-demand compute rather than long-lived processes.

docs/develop/go/workers/serverless-workers/cloud-run.mdx

@@ -15,15 +15,13 @@ tags:
 import { ReleaseNoteHeader } from '@site/src/components';
 
 <ReleaseNoteHeader featureName="serverlessWorkersCloudRun">
-  Cloud Run support is in Pre-release, and its APIs may change in backwards-incompatible ways.
-  Create a [support ticket](/evaluate/cloud/support#support-ticket) or contact your account team for access, and
-  [sign up for updates](https://temporal.io/pages/serverless-workers-updates) to hear when Cloud Run reaches Public Preview.
+  Cloud Run support is in Public Preview. APIs and configuration may change before the stable release.
 </ReleaseNoteHeader>
 
 On a [GCP Cloud Run worker pool](https://cloud.google.com/run/docs/resource-model#worker-pools), you run a standard long-lived Temporal Worker.
 Register Workflows and Activities the same way you would with any other Go Worker, and Temporal Cloud scales the pool up and down as work arrives and drains.
 
-A Cloud Run Worker needs no Cloud Run-specific package.
+A Cloud Run Worker needs no Cloud Run-specific runtime or handler.
 The one addition to a standard Worker is [Worker Versioning](/worker-versioning), which is required for Serverless Workers.
 
 For the end-to-end deployment guide covering the Worker Pool, IAM, and compute configuration, see [Deploy a Serverless Worker on GCP Cloud Run](/production-deployment/worker-deployments/serverless-workers/cloud-run).
@@ -112,7 +110,152 @@ func MyActivity(ctx context.Context, input MyInput) (string, error) {
 
 For how scale-in decisions are made, see [Serverless Workers on GCP Cloud Run](/serverless-workers/cloud-run#lifecycle).
 
-## Add observability {/* #add-observability */}
+## Configure OpenTelemetry {/* #opentelemetry */}
 
-A Cloud Run Worker emits the same traces and metrics as a Worker anywhere else.
-For how to configure metrics export and OpenTelemetry tracing interceptors, see [Observability - Go SDK](/develop/go/platform/observability) and the [SDK metrics reference](/references/sdk-metrics).
+Run an OpenTelemetry Collector as a sidecar in the Worker Pool. The Cloud Run OpenTelemetry plugin exports metrics and traces by OTLP gRPC to the Collector at `localhost:4317`. By default, it derives the service name from `OTEL_SERVICE_NAME`, `CLOUD_RUN_WORKER_POOL`, or `K_SERVICE`.
+
+Create both Cloud Run plugins before connecting, then add them to the Client options. Client plugins that implement
+`worker.Plugin` also apply to Workers created from that Client:
+
+<!--SNIPSTART go-cloud-run {"selectedLines": ["24-43"]}-->
+[gcp/cloudrun/worker/main.go](https://github.com/temporalio/samples-go/blob/gcp-cloud-run/gcp/cloudrun/worker/main.go)
+```go
+// ...
+	// Exports OTLP metrics and traces to the collector sidecar (defaults to localhost:4317).
+	otelPlugin, err := otel.NewPlugin(ctx, otel.PluginOptions{})
+	if err != nil {
+		log.Fatalln("Unable to create OpenTelemetry plugin", err)
+	}
+	// Sets the client identity to "<instanceID>@<revision>" from Cloud Run instance metadata.
+	idPlugin := id.NewCloudRunIDPlugin()
+
+	// A client plugin that also implements worker.Plugin is applied to workers automatically.
+	clientOptions, err := envconfig.LoadDefaultClientOptions()
+	if err != nil {
+		log.Fatalln("Unable to load Temporal client options", err)
+	}
+	clientOptions.Plugins = append(clientOptions.Plugins, otelPlugin, idPlugin)
+
+	c, err := client.Dial(clientOptions)
+	if err != nil {
+		log.Fatalln("Unable to create Temporal client", err)
+	}
+	log.Println("Client identity:", idPlugin.Metadata().Identity())
+```
+<!--SNIPEND-->
+
+Configure the Collector sidecar to receive OTLP gRPC on `localhost:4317`, export traces to Google Cloud, and export metrics to Google Managed Service for Prometheus:
+
+<!--SNIPSTART go-cloud-run-otel-collector-config-->
+[gcp/cloudrun/otel-collector-config.yaml](https://github.com/temporalio/samples-go/blob/gcp-cloud-run/gcp/cloudrun/otel-collector-config.yaml)
+```yaml
+# Google-Built OpenTelemetry Collector sidecar: metrics -> Managed Service for Prometheus, traces -> Cloud Trace.
+# Auth uses the worker-pool service account (ADC).
+receivers:
+    otlp:
+        protocols:
+            grpc:
+                endpoint: localhost:4317
+
+processors:
+    memory_limiter:
+        check_interval: 1s
+        limit_percentage: 65
+        spike_limit_percentage: 20
+    resourcedetection:
+        detectors: [gcp]
+        timeout: 10s
+    # Batch traces for throughput. Do NOT batch the cumulative-metrics pipeline: a shutdown flush
+    # could be merged with a recent periodic export of the same series and rejected as a duplicate.
+    batch/traces:
+        send_batch_size: 200
+        timeout: 5s
+    # Rename Temporal datapoint labels that collide with the target labels Managed Service for Prometheus injects (e.g. namespace).
+    transform/collision:
+        metric_statements:
+            - context: datapoint
+              statements:
+                  - set(attributes["exported_location"], attributes["location"])
+                  - delete_key(attributes, "location")
+                  - set(attributes["exported_cluster"], attributes["cluster"])
+                  - delete_key(attributes, "cluster")
+                  - set(attributes["exported_namespace"], attributes["namespace"])
+                  - delete_key(attributes, "namespace")
+                  - set(attributes["exported_job"], attributes["job"])
+                  - delete_key(attributes, "job")
+                  - set(attributes["exported_instance"], attributes["instance"])
+                  - delete_key(attributes, "instance")
+                  - set(attributes["exported_project_id"], attributes["project_id"])
+                  - delete_key(attributes, "project_id")
+    # The Telemetry API expects the Google Cloud project in gcp.project_id.
+    transform/set_project_id:
+        error_mode: ignore
+        trace_statements:
+            - set(resource.attributes["gcp.project_id"], resource.attributes["gcp.project.id"]) where resource.attributes["gcp.project.id"] != nil
+            - set(resource.attributes["gcp.project_id"], resource.attributes["cloud.account.id"]) where resource.attributes["gcp.project_id"] == nil and resource.attributes["cloud.account.id"] != nil
+
+exporters:
+    googlemanagedprometheus:
+    otlp_grpc:
+        endpoint: telemetry.googleapis.com:443
+        compression: none
+        balancer_name: pick_first
+        auth:
+            authenticator: googleclientauth
+
+extensions:
+    googleclientauth:
+    health_check:
+        endpoint: 0.0.0.0:13133
+
+service:
+    extensions: [googleclientauth, health_check]
+    pipelines:
+        metrics:
+            receivers: [otlp]
+            processors: [memory_limiter, resourcedetection, transform/collision]
+            exporters: [googlemanagedprometheus]
+        traces:
+            receivers: [otlp]
+            processors: [memory_limiter, resourcedetection, transform/set_project_id, batch/traces]
+            exporters: [otlp_grpc]
+    telemetry:
+        logs:
+            level: info
+```
+<!--SNIPEND-->
+
+On shutdown, stop the Worker and call `otelPlugin.Shutdown` with a deadline shorter than Cloud Run's termination window so telemetry can flush. For a Collector configuration that exports traces to Google Cloud and metrics to Google Managed Service for Prometheus, see the [Go Cloud Run sample](https://github.com/temporalio/samples-go/tree/gcp-cloud-run/gcp/cloudrun).
+
+## Set a Worker identity {/* #worker-identity */}
+
+Use the Cloud Run ID plugin to identify each Worker instance as `<instance-id>@<revision>`. The plugin reads Cloud Run environment variables and instance metadata once when the Client connects, then Workers created from that Client inherit the identity.
+
+Register the plugin on the Client options before connecting:
+
+```go
+import (
+	"log"
+
+	"go.temporal.io/sdk/client"
+	"go.temporal.io/sdk/contrib/envconfig"
+	"go.temporal.io/sdk/contrib/gcp/cloudrun/id"
+)
+
+// ...
+	clientOptions, err := envconfig.LoadDefaultClientOptions()
+	if err != nil {
+		log.Fatalln("Unable to load Temporal client options", err)
+	}
+	clientOptions.Plugins = append(clientOptions.Plugins, id.NewCloudRunIDPlugin())
+	c, err := client.Dial(clientOptions)
+	if err != nil {
+		log.Fatalln("Unable to create Temporal client", err)
+	}
+	defer c.Close()
+	// ...
+```
+
+The [preceding example](#opentelemetry) registers `id.NewCloudRunIDPlugin()` alongside the OpenTelemetry plugin.
+
+The plugin requires the Cloud Run metadata server, so it fails when the Worker runs outside Cloud Run. For a complete example, see the [Go Cloud Run sample](https://github.com/temporalio/samples-go/tree/gcp-cloud-run/gcp/cloudrun).

docs/develop/go/workers/serverless-workers/index.mdx

@@ -14,10 +14,7 @@ tags:
 import { ReleaseNoteHeader } from '@site/src/components';
 
 <ReleaseNoteHeader type="publicPreview">
-  AWS Lambda support is in Public Preview. GCP Cloud Run support is in Pre-release, and its APIs may change in
-  backwards-incompatible ways. To request Cloud Run access, create a [support ticket](/evaluate/cloud/support#support-ticket) or
-  contact your account team, and [sign up for updates](https://temporal.io/pages/serverless-workers-updates) to hear
-  when Cloud Run reaches Public Preview.
+  AWS Lambda and GCP Cloud Run support are in Public Preview.
 </ReleaseNoteHeader>
 
 Serverless Workers run on ephemeral, on-demand compute rather than long-lived processes.